Looking at the service manuals, it seems that the heater is run through the fuel pump relay, and it's own 7.5A fuse. Is this correct? I had a feeling that there was another relay for just the heater?
1997 2.0 16v, sorry. Didn't mention that at first.
Where is the best place to get a new sensor? I'd rather get a genuine part that will be a straight swap, than a universal sensor that I'll have to splice wires into. (might do that next time)
Do the dealers keep these in stock, or is it a wait a few weeks job? (obviously varies between dealers, but just if you've had any experience).
Looking at the diags, I should be able to measure heater resistance at the fuse (between one terminal and GND) to get a rough idea before going for a crawl (obviously it'll be higher impeadance than the element itself, but if it's OC, then there's a problem).
What's the normal failure mode of the sensor? Fouling, heater failure, low output?
Thanks for all the help so far...
Car legal for another two days